Hot bulb engines helped usher in the Industrial Age and served as a missing link of sorts between primitive and modern engines. The machines are quirky, temperamental and irascible. But they're also well-loved by users and collectors, a deserving fate for what has been described as a workhorse for early technology.

Crankshaft bearings support the crankshaft, one of the components that makes your car's engine rotate. For such an important part, you want to be sure they're working properly. But how long do they last, and how can you tell if they need replacing?